Recent geological studies have revealed that Qinghai Saishitang copper mining area is a deformation zone with several superimposed folds.To provide basic geological support for mine exploration programs,integrated tectonic analysis method drawn on outcrop structural analysis is adopted in this paper.Middle-Early Triassic rocks in mining area of poor outcrop condition are classified into four phases of fold association styles.All phases of folds are involved to produce various superimposed structures in light of outcrop and regional scale. In most cases, the presence of the Ramsy′s Type 3 superposition,which is formed by the overlay of F2 folds on earlier F1 ones,suggesting that the two may be result of two successive deformation phases in one tectonic cycle and representing a crustal deformation mechanism transition from delamination shear to horizontal shortening.The intrusion and emplacement of Indosinian magmatic complex also took place between two deformation phases,which is probably a response to the far field transition from subduction to collision of the west Qinling and Qaidam blocks in the Indosinian tectonic period.The fold structure plays an important role on the formation,reconstruction and preservation of the polymetallic deposit in Saishitang mining area.%新的资料揭示,青海赛什塘铜矿区是褶皱叠加变形区。为矿山勘探工作提供基础地质支撑,采用露头构造解析基础上的构造综合分析方法,在露头条件欠佳的矿区中下三叠统中首次厘定出4期褶皱组合样式,形成露头和区域尺度上的各类叠加构造。第二期褶皱(F2)叠加在第一期褶皱(F1)之上,主要形成 Ramsy(Ramsay et al.,1987)的第三类叠加,表明二者可能是同一构造事件中连续的2阶段变形作用的结果,代表了从分层剪切到横向缩短的地壳变形机制转换过程,其间同时发生了印支期岩浆杂岩的侵入就位,推测是对区域上印支期西秦岭地块与柴达木地块之间从俯冲向碰撞转换的远程效应的响应。褶皱构造对赛什塘铜多金属矿的形成、改造和保存都起了重要作用。
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